they are different. Crank angle sensors are usually near the front crank pulley, and work off a magnet attached to it. the cam sensor will be in a position close to the cam, in the head very close to the cam so it can pick up the magnetic pulse from the cam. Faulty sensors will cause similar symptoms, but the crank sensor will stop your motor when it finally s***s itself, and is the most common failure, especially because it is low, gets covered in oil, gets wet when you drive thru water etc.